Method of manufacturing electronic device

ABSTRACT

A method of manufacturing an electronic device includes providing a substrate, providing an electronic unit having a chip and at least one bonding pin is provided, mounting the electronic unit on the substrate through the at least one bonding pin, and applying an adhesive material into a space between the chip and the substrate by a coating process after mounting the electronic unit on the substrate.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 17/482,438, filed on Sep. 23, 2021. The content of the applicationis incorporated herein by reference.

BACKGROUND OF THE DISCLOSURE 1. Field of the Disclosure

The present disclosure relates to a method of manufacturing anelectronic device, in particular to a method of manufacturing anelectronic device by applying an adhesive material in the space betweena chip and a substrate.

2. Description of the Prior Art

With the development of science and technology and the demand of use, anelectronic device made with electronic units has gradually becomepopular in life. In order to increase the yield of the electronicdevice, it is one of the important issues for manufacturers to cope withhow to develop an electronic device with greater robustness between theelectronic units and the substrate.

SUMMARY OF THE DISCLOSURE

In view of this, it is needed to increase the fabrication yield of theelectronic device to facilitate the innovation of the electronic device.For example, an improved method may be proposed to strengthen thefixation between the electronic units and the substrate.

Some embodiments of the present disclosure provide a method ofmanufacturing an electronic device. First a substrate is provided; thenan electronic unit having a chip and at least one bonding pin isprovided. The electronic unit is mounted on the substrate through the atleast one bonding pin. An adhesive material is applied into a spacebetween the chip and the substrate by a coating process after mountingthe electronic unit on the substrate.

According to the embodiments of the method of manufacturing theelectronic device of the present disclosure, by applying the adhesivematerial into the space between the chip and the substrate, therobustness between the electronic units and the substrate may beimproved. Accordingly, the quality of the electronic units in theelectronic device may be improved to facilitate the technologicaldevelopment and innovation of the electronic device.

These and other objectives of the present disclosure will no doubtbecome obvious to those of ordinary skill in the art after reading thefollowing detailed description of the embodiment that is illustrated inthe various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 to FIG. 4 are schematic flowcharts of the first embodiment of themethod for manufacturing an electronic device according to the presentdisclosure, which show schematic cross-sectional views of the electronicdevice.

FIG. 3A is a schematic flowchart corresponding to FIG. 3 of a method formanufacturing an electronic device according to the present disclosure,which shows a schematic cross-sectional view of the electronic device.

FIG. 5 to FIG. 8 are schematic flowcharts of the second embodiment ofthe method for manufacturing an electronic device according to thepresent disclosure, which show schematic cross-sectional views of theelectronic device.

FIG. 9 to FIG. 10 are schematic flowcharts of the third embodiment ofthe method for manufacturing an electronic device according to thepresent disclosure, which show schematic cross-sectional views of theelectronic device.

FIG. 11 to FIG. 12 are schematic flowcharts of the fourth embodiment ofthe method for manufacturing an electronic device according to thepresent disclosure, which show schematic cross-sectional views of theelectronic device.

FIG. 13 is a schematic flowchart of the fifth embodiment of a method formanufacturing an electronic device according to the present disclosure,which shows a schematic cross-sectional view of the electronic device.

DETAILED DESCRIPTION

The present disclosure may be understood by reference to the followingdetailed description, taken in conjunction with the drawings asdescribed below. It is noted that, for purposes of illustrative clarityand being easily understood by the readers, various drawings of thisdisclosure show a portion of the touch display device, and certainelements in various drawings may not be drawn to scale. In addition, thenumber and dimension of each device shown in drawings are onlyillustrative and are not intended to limit the scope of the presentdisclosure.

Certain terms are used throughout the description and following claimsto refer to particular components. As one skilled in the art willunderstand, electronic equipment manufacturers may refer to a componentby different names. This document does not intend to distinguish betweencomponents that differ in name but not function. In the followingdescription and in the claims, the terms “include”, “comprise” and“have” are used in an open-ended fashion, and thus should be interpretedto mean “include, but not limited to”.

When a component or a film layer is referred to as “disposed on anothercomponent or another film layer” or “connected to another component oranother film layer”, it can mean that the component or film layer isdirectly disposed on another component or film layer, or directlyconnected to another component or film layer, or there may be othercomponents or film layers in between. In contrast, when a component issaid to be “directly disposed on another component or film” or “directlyconnected to another component or film”, there is no component or filmbetween the two. When a component or a film layer is referred to as“coupled to” another component or another film layer, it can mean thatthe component or film layer is directly connected to another componentor film layer, or indirectly connected to another component or filmlayer via one or more components.

The terms “about”, “substantially”, “equal”, or “same” generally meanwithin 20% of a given value or range, or mean within 10%, 5%, 3%, 2%,1%, or 0.5% of a given value or range.

Although terms such as first, second, third, etc., may be used todescribe diverse constituent elements, such constituent elements are notlimited by the terms. The terms are used only to discriminate aconstituent element from other constituent elements in thespecification. The claims may not use the same terms, but instead mayuse the terms first, second, third, etc. with respect to the order inwhich an element is claimed. Accordingly, in the following description,a first constituent element may be a second constituent element in aclaim.

The technical features in different embodiments described in thefollowing may be replaced, recombined, or mixed with one another toconstitute another embodiment without departing from the spirit of thepresent disclosure.

FIG. 1 to FIG. 4 are schematic flowcharts of the first embodiment of themethod for manufacturing an electronic device according to the presentdisclosure, and show schematic cross-sectional views of the electronicdevice. The electronic device of the present disclosure may include adisplay device, a backlight device, an antenna device, a sensing device,or a tiled device, but the present disclosure is not limited thereto.The electronic device may be a bendable or flexible electronic device.The display device may be a non-self-luminous display device or aself-luminous display device. The antenna device may be a liquid crystalantenna device or a non-liquid crystal antenna device. The sensingdevice may be a sensing capacitor, a light, a thermo or an ultra-soundsensing device, but the present disclosure is not limited thereto. Anelectronic unit may include a passive element and an active element, forexample, a capacitor, a resistor, an inductor, a diode, and atransistor. The diode may include a light emitting diode or aphotodiode. The light emitting diode may include, for example, anorganic light emitting diode (OLED), a mini light-emitting diode, (miniLED), and a micro LED or quantum dots (QD, for example, QLED, QDLED),but the present disclosure is not limited thereto. The tiled device maybe, for example a display tiled device or an antenna tiled device, butthe present disclosure is not limited thereto. It should be noted thatthe electronic device may be any combination of the above, but thepresent disclosure is not limited thereto. The display device is takenas an example of the electronic device in the present disclosure, butthe present disclosure is not limited thereto.

First, as shown in FIG. 1 , a substrate 110 is provided. The substrate110 may be a transparent or opaque organic material or inorganicmaterial, or a rigid material or a flexible material. The substrate mayinclude, for example, polyimide (PI), polycarbonate (PC), polyethyleneterephthalate (PET), other known suitable materials or a combinationthereof, but the present disclosure is not limited thereto. Thesubstrate 110 may also be a rigid material, such as glass, sapphire,ceramic or plastic, or any suitable material. Optionally, the substrate110 may include various elements for use in electronic devices, such aswires (not shown), polysilicon (not shown), a bonding pad 111, a bondingpad 112, a bonding pad 113, a bonding pad 114, a bonding pad 115, abonding pad 116, a source (not shown), a drain (not shown), a commonelectrode (not shown), a pixel defining layer (not shown) or alimitation layer (not shown), but the present disclosure is not limitedthereto.

Next, a plurality of electronic units, such as an electronic unit 121,an electronic unit 122 and an electronic unit 123, are provided. FIG. 1illustrates that there are three electronic units disposed on thesubstrate 110, but the present disclosure is not limited thereto. Eachelectronic unit may have a chip and at least one bonding pin. Forexample, the electronic unit 121 may have a chip 121C and at least onebonding pin. FIG. 1 illustrates an example of an electronic unit 121having two bonding pins (a bonding pin 121A and a bonding pin 121B), butthe present disclosure is not limited thereto. Similarly, the electronicunit 122 may have a chip 122C and two bonding pins, such as a bondingpin 122A/a bonding pin 122B, and the electronic unit 123 may have a chip123C and two bonding pins, such as a bonding pin 123A/a bonding pin123B, but the present disclosure is not limited thereto.

Each of the electronic units may be mounted to the substrate 110 throughthe bonding pin(s). For example, the electronic unit 121 may berespectively mounted to the corresponding bonding pad 111/bonding pad112 of the substrate 110 through the bonding pin 121A/bonding pin 121B;the electronic unit 122 may be respectively mounted to the correspondingbonding pad 113/bonding pad 114 of the substrate 110 through the bondingpin 122A/bonding pin 122B; the electronic unit 123 may be respectivelymounted to the corresponding bonding pad 115/the bonding pad 116 of thesubstrate 110 through the bonding pin 123A/the bonding pin 123B, but thepresent disclosure is not limited thereto. The electronic unit may bephysically and electrically connected to the bonding pads of thesubstrate 110 through the bonding pins. In some embodiments, the bondingpin(s) of each electronic unit and the bonding pad(s) of the substrate110 may be bonded together through solder, but the present disclosure isnot limited thereto. Or, in some embodiments, the bonding pin(s) of eachelectronic unit and the bonding pad(s) of the substrate 110 may bedirectly bonded together through metal diffusion (such as Cu—Cubonding), but the present disclosure is not limited thereto.

As the substrate structure shown in FIG. 1 , between each chip (forexample, the chip 121C of the electronic unit 121, the chip 122C of theelectronic unit 122, or the chip 123C of the electronic unit 123) andthe substrate 110, there may be a space. For example, a space 121S isdisposed between the chip 121C and the substrate 110, a space 122S isdisposed between the chip 122C and the substrate 110 or a space 123S isdisposed between the chip 123C and the substrate 110, but the presentdisclosure is not limited thereto. In some embodiments, the spacesbetween the chips of the electronic units and the substrate may not belarge. For example, the distance between the chips of the electronicunits and the substrate is approximately the sum of the height(thickness) of a bonding pad and a bonding pin, and the distance may beless than or equal to 3 micrometers (≤3 μm), but the present disclosureis not limited thereto. In the current technology, if the space betweenthe chips of the electronic units and the substrate is relatively small,it may affect the caulking property of the adhesive material. If thecaulking property of the adhesive material is poor, it may bedetrimental to the robustness between the electronic units and thesubstrate. The present disclosure provides a method to improve therobustness between the electronic units and the substrate, the detailsare described later.

According to the present disclosure, each electronic unit for examplemay include (but is not limited to) a micro LED. Each micro LED may beused to define a sub-pixel or regarded as a sub-pixel, to generate lightof a predetermined wavelength. For example, each electronic unit maycorrespond to one of a red pixel, a green pixel, a blue pixel, a whitepixel, or other colors or wavelengths or a combination thereof, but thepresent disclosure is not limited thereto. FIG. 1 shows that theelectronic unit 121 may be one of a red pixel, a green pixel, a bluepixel and a white pixel, the electronic unit 122 may be one of a redpixel, a green pixel, a blue pixel or a white pixel, and the electronicunit 123 may be one of a red pixel, a green pixel, a blue pixel or awhite pixel, but the present disclosure is not limited thereto.

After the electronic units are mounted to the substrate 110, an adhesivematerial may be applied to each space which is disposed between eachchip and the substrate 110. FIG. 1 shows an example to apply the liquidadhesive material 130 by an inkjet printing method, but the presentdisclosure is not limited thereto. In a variant embodiment, the methodfor applying the liquid adhesive material 130 may also include coating,screen printing or other suitable known processes, and theabove-mentioned process may be applied to other embodiments of thepresent disclosure for applying the adhesive material 130 and is notelaborated again. The method proposed in the present disclosure isbeneficial to increase the caulking property of the adhesive material130, and therefore, is beneficial to the robustness between eachelectronic unit and the substrate 110. The adhesive material 130 may bea resin with high optical transmittance. For example, the opticaltransmittance of the adhesive material 130 may be greater than or equalto 95% (optical transmittance 95%), but the present disclosure is notlimited thereto. In other words, the optical transmittance of theadhesive material 130 for light with a wavelength of 380 nm to 780 nm isgreater than or equal to 95%. Alternatively, the optical transmittanceof the adhesive material 130 for light with a wavelength of 550 nm isgreater than or equal to 95%. The adhesive material 130 may be amaterial such as acrylic, silicone, silicon, or epoxy resin, but thepresent disclosure is not limited thereto. The adhesive material 130 mayhave a suitable viscosity at room temperature, for example, in a rangebetween 1 cP and 500 cP, in a range between 1 cP and 100 cP, or in arange between 1 cP and 50 cP, but the present disclosure is not limitedthereto. The adhesive material 130 may have a viscosity which isthermally changeable. For example, upon heating the viscosity of theadhesive material 130 may be adjusted to, such as between 8 cP and 12cP. The adjustment of the viscosity of the adhesive material 130 maymatch the size of the nozzle 141 of the inkjet machine 140, toappropriately apply the adhesive material 130 to each space disposedbetween each chip and the substrate 110. The droplet size of thedroplet-shaped adhesive material 130 may be less than or equal to 30micrometers (30 μm).

Since the adhesive material 130 may be a liquid of an appropriateviscosity, the droplet-shaped adhesive material 130 may slowly fill thespace 121S, the space 122S and the space 123S by natural capillaryphenomenon or gravity after the adhesive material 130 is applied by theinkjet printing method. For example, the adhesive material 130 may fillup the space 121S, the space 122S and the space 123S. In addition, theadhesive material 130 may also fill the gaps between the electronic unit121, the electronic unit 122 and the electronic unit 123, or theadhesive material 130 may stay on the top surfaces of the electronicunits. For example, the adhesive material 130 may stay on the topsurface 121T of the electronic unit 121, the top surface 122T of theelectronic unit 122, or the top surface 123T of the electronic unit 123.When the adhesive material 130 fills the gaps between adjacentelectronic units, the top surfaces of the electronic units may be higherthan the top surface 130S of the adhesive material 130 (shown in FIG. 2). FIG. 2 shows that the adhesive material 130 fills up the spacesbetween the chips and the substrate 110, and fills the gaps between theelectronic units, and may also stay on the top surfaces of theelectronic units, for example, stays on the top surface 121T of theelectronic unit 121 in FIG. 2 after the adhesive material is applied bythe inkjet printing method. Optionally, an external vacuum or pressuremay facilitate the droplet-shaped adhesive material 130 to make theadhesive material 130 fill the spaces and gaps.

In some embodiments, the adhesive material 130 may further cover the topsurfaces of the electronic units. FIG. 3 illustrates the application ofa sufficient amount of the adhesive material by inkjet printing methodto make the adhesive material fill the spaces between the chips and thesubstrate 110, fill the gaps between the electronic units, and alsocover the top surfaces of the electronic units, so it may be regarded asa packaging structure. For example, the nozzle 141 of the inkjet machine140 shown in FIG. 1 may be controlled to apply the amount of theadhesive material 130 so that the adhesive material 130 may fill up thespace 121S, the space 122S and the space 123S, and may fill the gapsbetween the electronic unit 121, the electronic unit 122 and theelectronic unit 123 and further cover the top surface 121T of theelectronic unit 121, the top surface 122T of the electronic unit 122, orthe top surface 123T of the electronic unit 123. In some embodiments,the top surface 130S of the adhesive material 130 may be higher than thetop surfaces of the electronic units. Since the top surfaces of theelectronic units may generally be regarded as the light-emittingsurfaces, in order to reduce the light loss caused by the adhesivematerial 130 covering the top surfaces, it is preferable to select anadhesive material of a light transmittance greater than or equal to 95%in this embodiment, but the present disclosure is not limited thereto.If a smaller amount of adhesive material is applied by the inkjetprinting method, it corresponds to the embodiment as shown in FIG. 2.

In some embodiments, if the adhesive material 130 covers the top surfaceof the electronic units, a post process may be optionally carried out.FIG. 4 shows a structure after the post process. The top surface 130S ofthe adhesive material 130 is as high as the top surfaces of theelectronic units to form a coplanar structure. The optional post processmay be a surface leveling method. The optional post process, such aschemical etching, mechanical polishing, or plasma treatment, may becarried out to lower the top surface 130S of the adhesive material 130so that the top surface 130S of the adhesive material 130 may be roughly(or substantially) close to the top surfaces of the electronic units, ormake the top surface 130S of the adhesive material 130 as high as thetop surfaces of the electronic units, to become a coplanar structure,and to expose the top surface 121T of the electronic unit 121, to exposethe top surface 122T of the electronic unit 122, or to expose the topsurface 123T of the electronic unit 123.

In some embodiments, the curing step of the adhesive material 130 mayalso be carried out. An appropriate curing step may be carried out byreferring to the curing conditions of various adhesive materials 130,such as radiation, heating, or a mixture of the two, so that the curedadhesive material 130 may make the electronic units fixed on thesubstrate to reinforce the bonding strength between the electronic unitsand the substrate. FIG. 2 illustrates that the electronic device 100Aincludes a cured adhesive material 130, and the top surface 130S may belower than the top surfaces of the electronic units. FIG. 3 illustratesthat the electronic device 100B includes a cured adhesive material 130,and the top surface 130S may be higher than the top surfaces of theelectronic units. FIG. 4 illustrates that the electronic device 100Cincludes the cured adhesive material 130, and the top surface 130S alongwith the top surfaces of the electronic units forms a coplanarstructure.

FIG. 3A is a schematic flowchart corresponding to FIG. 3 of a method formanufacturing an electronic device according to the present disclosure,which shows a schematic cross-sectional view of the electronic device.Furthermore, another optional adhesive material 130A, such as an opticalclear resin (OCR), may be used to bond the electronic device 100B toanother optical substrate 160 after the curing step of the adhesivematerial 130. The optical substrate 160 may include a color conversionlayer, a color filter layer, and a bank 163, but the present disclosureis not limited thereto. FIG. 3A shows that the light conversion layermay include a light conversion layer 161A, a light conversion layer 161Band a light conversion layer 161C. The color filter layer may include acolor filter layer 162A, a color filter layer 162B and a color filterlayer 162C, but the present disclosure is not limited thereto. The lightconversion layer 161A and the color filter layer 162A may correspond tothe electronic unit 121, the light conversion layer 161B and the colorfilter layer 162B may correspond to the electronic unit 122, and thelight conversion layer 161C and the color filter layer 162C maycorrespond to the electronic unit 123. The light conversion layer mayconvert blue light to green light or to red light through the lightconversion particles therein, such as quantum dot particles (QDparticles) when the electronic unit 121, the electronic unit 122 and theelectronic unit 123 are blue pixels which emits blue light, but thepresent disclosure is not limited thereto.

FIG. 5 to FIG. 8 are schematic flowcharts of the second embodiment ofthe method for manufacturing an electronic device according to thepresent disclosure, which show schematic cross-sectional views of theelectronic device. In the second embodiment of the method formanufacturing an electronic device of the present disclosure, a pixeldefinition layer (PDL) may be further provided between adjacentelectronic units.

First, as shown in FIG. 5 , a substrate 110 is provided. The substrate110 may include a bonding pad 111, a bonding pad 112, a bonding pad 113,a bonding pad 114, a bonding pad 115, and a bonding pad 116. Thesubstrate 110 may be a transparent or opaque organic material orinorganic material, or the substrate 110 may be a rigid material or aflexible material. Please refer to the first embodiment for the detailsof the substrate 110, so they are not elaborated again. Second, aplurality of electronic units are provided, such as an electronic unit121, an electronic unit 122, and an electronic unit 123. Each electronicunit may have a chip and at least one bonding pin. For example, theelectronic unit 121 may have a chip 121C and two bonding pins such as abonding pin 121A/a bonding pin 121B, the electronic unit 122 may have achip 122C and two bonding pins such as a bonding pin 122A/a bonding pin122B), the electronic unit 123 may have a chip 123C and two bonding pinssuch as a bonding pin 123A/a bonding pin 123B, but the presentdisclosure is not limited thereto. Each of the plurality of electronicunits may be mounted to the substrate 110 through the bonding pin(s).For example, the electronic unit 121 may be respectively mounted to thecorresponding bonding pad 111/bonding pad 112 of the substrate 110through the bonding pin 121A/bonding pin 121B; the electronic unit 122may be respectively mounted to the corresponding bonding pad 113/bondingpad 114 of the substrate 110 through the bonding pin 122A/bonding pin122B; the electronic unit 123 may be respectively mounted to thecorresponding bonding pad 115/bonding pad 116 of the substrate 110through the bonding pin 123A/bonding pin 123B, but the presentdisclosure is not limited thereto. Between each chip and the substrate110 there may be a space, such as a space 121S between the chip 121C andthe substrate 110, a space 122S between the chip 122C and the substrate110 or a space 123S between the chip 123C and the substrate 110, but thepresent disclosure is not limited thereto. Please refer to the firstembodiment for the details of the electronic unit, so they are notelaborated again.

Between adjacent electronic units, a pixel defining layer may be furtherincluded. For example, the pixel defining layer 151 may be located onone side of the electronic unit 121; the pixel defining layer 152 may belocated between the electronic unit 121 and the electronic unit 122; thepixel defining layer 153 may be located between the electronic unit 122and the electronic unit 123; the pixel defining layer 154 may be locatedbeside the electronic unit 123. Each pixel defining layer, such as thepixel defining layer 151, the pixel defining layer 152, the pixeldefining layer 153 and the pixel defining layer 154, may include variousorganic or inorganic materials. The pixel defining layer may be atransparent pixel defining layer if no pigment particles are added.Conversely, it may be a colored pixel defining layer, such as a whitepixel defining layer or a gray pixel defining layer if pigment particlesare added to the pixel defining layer. Each pixel defining layer may belocated on the substrate 110 or in direct contact with the substrate110, but the present disclosure is not limited thereto. The top surfacesof the pixel defining layers may not be lower than the top surfaces ofthe electronic units. For example, the top surface 1515 of the pixeldefining layer 151, the top surface 152S of the pixel defining layer152, the top surface 153S of the pixel defining layer 153 and the topsurface 154S of the pixel defining layer 154 may not be lower than thetop surface 121T of the electronic unit 121, the top surface 122T of theelectronic unit 122 or the top surface 123T of the electronic unit 123,but the present disclosure is not limited thereto. The pixel defininglayers may be used for light shielding, reducing the possibility oflight mixing of adjacent electronic units to affect the image quality ofthe electronic device. The pixel defining layer may also be used forreflection to improve the light utilization efficiency of the electronicunits. In some embodiments, the gaps between the pixel defining layersand the adjacent electronic units may not be large, for example, lessthan 10 micrometers (<10 μm), but the present disclosure is not limitedthereto. A relatively smaller gap between the pixel defining layer andthe adjacent electronic unit may affect the caulking property of theadhesive material. If the caulking property of the adhesive material ispoor, it may be detrimental to the robustness between the electronicunits and the substrate.

Then, an adhesive material 130 may be applied to the spaces and gapsbetween the chips, the pixel defining layers and the substrate 110. FIG.5 illustrates the application of the liquid adhesive material by aninkjet printing method, but the present disclosure is not limitedthereto. The method proposed in the present disclosure is beneficial toincrease the caulking property of the adhesive material so as to bebeneficial to the robustness between the micro electronic units and thesubstrate. The adhesive material 130 may be a resin with high opticaltransmittance. For example, the optical transmittance of the adhesivematerial 130 may be greater than or equal to 95% (optical transmittance95%), but the present disclosure is not limited thereto. The adhesivematerial 130 may be a material such as acrylic, silicone, silicon, orepoxy resin, but the present disclosure is not limited thereto. Theadhesive material 130 may have a suitable viscosity at room temperature,for example, in a range between 1 cP and 500 cP, in a range between 1 cPand 100 cP, or in a range between 1 cP and 50 cP, but the presentdisclosure is not limited thereto. The adhesive material 130 may have aviscosity which is thermally changeable. For example, upon heating theviscosity of the adhesive material 130 may be adjusted to, such as arange between 8 cP and 12 cP. The adjustment of the viscosity of theadhesive material 130 may match the size of the nozzle 141 of the inkjetmachine 140, to appropriately apply the adhesive material 130 to eachspace and to each gap disposed between each chip, the pixel defininglayers and the substrate 110. The droplet size of the droplet-shapedadhesive material 130 may be less than or equal to 30 micrometers (30μm).

Since the adhesive material 130 may be a liquid of an appropriateviscosity, the adhesive material 130 may slowly fill the space 121S, thespace 122S and the space 123S by natural capillary phenomenon or gravityafter the adhesive material 130 is applied by the inkjet printingmethod. For example, the adhesive material 130 may fill up the space121S, the space 122S and the space 123S. In addition, the adhesivematerial 130 may also fill the gaps between the electronic units and thepixel defining layers, or the adhesive material 130 may stay on the topsurfaces of the electronic units. For example, the adhesive material 130may stay on the top surface 121T of the electronic unit 121, on the topsurface 122T of the electronic unit 122, or on the top surface 123T ofthe electronic unit 123. The adhesive material 130 may also stay on thetop surfaces of the pixel defining layers. For example, the adhesivematerial 130 may stay on the top surface 151S of the pixel defininglayer 151, on the top surface 152S of the pixel defining layer 152, andon the top surface 153S of the pixel defining layer 153 or on the topsurface 154S of the pixel defining layer 154. In some embodiments, thetop surfaces of the electronic units may be higher than the top surface130S of the adhesive material 130 (shown in FIG. 2 ). FIG. 6 shows thatthe adhesive material 130 fills up the spaces, and fills in the gapsbetween the electronic units and the pixel defining layers, and may alsostay on the top surface 121T of the electronic unit 121 and on the topsurface 152S of the pixel defining layer 152, but the present disclosureis not limited thereto. Optionally, an external vacuum or pressure mayfacilitate the adhesive material 130 to make the adhesive material 130fill the spaces and gaps better.

In some embodiments, the adhesive material 130 may further cover the topsurfaces of the electronic units. FIG. 7 illustrates the application ofa sufficient amount of the adhesive material by inkjet printing methodto make the adhesive material fill the spaces, fill the gaps between theelectronic units and the pixel defining layers, and cover the topsurfaces of the electronic units, so it may be regarded as a packagingstructure. For example, the nozzle 141 of the inkjet machine 140 may becontrolled to apply the amount of the adhesive material 130 so that theadhesive material 130 may fill up the space 121S, the space 122S and thespace 123S, and may fill the gaps between the electronic units and thepixel defining layers, and further cover the top surface 121T of theelectronic unit 121, the top surface 122T of the electronic unit 122, orthe top surface 123T of the electronic unit 123. The adhesive material130 may also cover the top surface 1515 of the pixel defining layer 151,the top surface 152S of the pixel defining layer 152, the top surface153S of the pixel defining layer 153 or the top surface 154S of thepixel defining layer 154. After the adhesive material 130 fills thegaps, the top surface 130S of the adhesive material 130 may be higherthan the top surfaces of the electronic units or higher than the topsurface of the pixel defining layer 153. Since the top surfaces of theelectronic units may generally be regarded as light-emitting surfaces,in order to reduce the light loss caused by the adhesive material 130covering the top surfaces, it is preferable to select an adhesivematerial of a light transmittance greater than or equal to 95% in thisembodiment, but the present disclosure is not limited thereto. If asmaller amount of adhesive material is applied by the inkjet printingmethod, it corresponds to the embodiment as shown in FIG. 6 .Optionally, an external vacuum or pressure may facilitate the adhesivematerial 130 to make the adhesive material 130 fill the spaces and gapsbetter.

In some embodiments, if the adhesive material 130 covers the topsurfaces of the electronic units, a post process may be optionallycarried out. FIG. 8 shows a structure after the post process. The topsurface 130S of the adhesive material 130 is as high as the top surfacesof the electronic units to form a coplanar structure. The optional postprocess may be a surface leveling method. The optional post process,such as chemical etching, mechanical polishing, or plasma treatment, maybe carried out to lower the top surface 130S of the adhesive material130 so that the top surface 130S of the adhesive material 130 may beroughly (or substantially) close to the top surfaces of the electronicunits, or make the top surface 130S of the adhesive material 130 as highas the top surfaces of the electronic units, to become a coplanarstructure, and to expose the top surface 121T of the electronic unit121, expose the top surface 122T of the electronic unit 122 or exposethe top surface 123T of the electronic unit 123. In some embodiments,the top surface 1515 of the pixel defining layer 151, the top surface152S of the pixel defining layer 152, the top surface 153S of the pixeldefining layer 153 or the top surface 154S of the pixel defining layer154 may be exposed as well.

In some embodiments, the curing step of the adhesive material 130 mayalso be carried out. An appropriate curing step may be carried out byreferring to the curing conditions of various adhesive materials 130,such as radiation, heating, or a mixture of the two, so that the curedadhesive material 130 may make the electronic units fixed on thesubstrate to reinforce the bonding strength between the electronic unitsand the substrate. FIG. 6 illustrates that the electronic device 101Aincludes a cured adhesive material 130, and the top surface 130S may belower than the top surfaces of the electronic units. FIG. 7 illustratesthat the electronic device 101B includes a cured adhesive material 130,and the top surface 130S may be higher than the top surfaces of theelectronic units. FIG. 8 illustrates that the electronic device 101Cincludes the cured adhesive material 130, and the top surface 130S alongwith the top surfaces of the electronic units forms a coplanarstructure.

FIG. 9 to FIG. 10 are schematic flowcharts of the third embodiment ofthe method for manufacturing an electronic device according to thepresent disclosure, which show schematic cross-sectional views of theelectronic device. In the third embodiment of the method formanufacturing an electronic device according to the present disclosure,the application of the adhesive material may involve a sheet of theadhesive material in a solid state.

FIG. 9 shows an example to apply the adhesive material in a form a sheetin a solid state, but the present disclosure is not limited thereto. Themethod proposed in the present disclosure is beneficial to increase thecaulking property of the adhesive material, and therefore, is beneficialto the robustness between each electronic units and the substrate. Forexample, an adhesive material in a solid state is provided, and a sheetof the solid adhesive material is attached to a plurality of electronicunits. The sheet 131 may be an optical transparent adhesive, such asoptically clear adhesive (OCA), but the present disclosure is notlimited thereto. The optical transmittance of the sheet 131 may begreater than or equal to 95% (optical transmittance≥95%), but thepresent disclosure is not limited thereto. In some embodiments, thethickness of the sheet 131 may be less than 10 micrometers (<10 μm). Thesheet 131 may be in a solid state at room temperature, but the presentdisclosure is not limited thereto. The sheet 131 may be softened andhave a suitable viscosity upon heating to convert the sheet 131 from asolid state to a liquid state. For example, the solid sheet 131 may besoftened to become a liquid adhesive material 130 after the heating stepto adjust the viscosity to, such as a range between 8 cP and 12 cP.

Since the adhesive material 130 may be a liquid of an appropriateviscosity, the adhesive material 130 may slowly fill the spaces betweenthe chips and the substrate after the softened sheet 131 becomes theliquid adhesive material 130. For example, the adhesive material 130 mayslowly fill into and fill up the space 121S, the space 122S and thespace 123S by natural capillary phenomenon or gravity. In addition, theadhesive material 130 may also fill the gaps between the electronic unit121, the electronic unit 122 and the electronic unit 123, or theadhesive material 130 may stay on the top surfaces of the electronicunits. For example, the adhesive material 130 may stay on the topsurface 121T of the electronic unit 121, on the top surface 122T of theelectronic unit 122, or on the top surface 123T of the electronic unit123. The top surfaces of the electronic units may be higher than the topsurface 130S of the adhesive material 130 (shown in FIG. 2 ).

In some embodiments, the adhesive material 130 may further cover the topsurfaces of the electronic units. As shown in FIG. 3 , the adhesivematerial may fill the spaces, fill the gaps between the electronicunits, and further cover the top surfaces of the electronic units. Theamount of the adhesive material 130 may be controlled so that theadhesive material 130 may fill up the space 121S, the space 122S and thespace 123S, and may fill the gaps between the electronic unit 121, theelectronic unit 122 and the electronic unit 123 and further cover thetop surface 121T of the electronic unit 121, the top surface 122T of theelectronic unit 122 or the top surface 123T of the electronic unit 123.The top surface 130S of the adhesive material 130 may be higher than thetop surfaces of the electronic units after the adhesive material 130fills the spaces and the gaps. Optionally, an external vacuum orpressure may facilitate the liquid adhesive material 130 to make theadhesive material 130 fill the spaces and gaps better.

In another embodiment of the present disclosure, a post process may beoptionally carried out if the adhesive material 130 covers the topsurfaces of the electronic units. FIG. 4 shows that the top surface 130Sof the adhesive material 130 is as high as the top surface of theelectronic unit to form a coplanar structure after the post process. Theoptional post process may be a surface leveling method. Please refer toFIG. 4 for the details of the post process, so they are not elaboratedagain.

In some embodiments, the curing step of the adhesive material 130 mayalso be carried out. An appropriate curing step may be carried out byreferring to the curing conditions of various adhesive materials 130,such as radiation, heating, or a mixture of the two, so that the curedadhesive material 130 may make the electronic units fixed on thesubstrate to reinforce the bonding strength between the electronic unitsand the substrate. Please refer to FIG. 2 , FIG. 3 or FIG. 4 for thedetails, so they are not elaborated again.

FIG. 11 to FIG. 12 are schematic flowcharts of the fourth embodiment ofthe method for manufacturing an electronic device according to thepresent disclosure, which show schematic cross-sectional views of theelectronic device. In the fourth embodiment of the method formanufacturing an electronic device of the present disclosure, the methodof applying the adhesive material may involve a sheet of an adhesivematerial in a solid state on the substrate including the pixel defininglayer.

FIG. 11 shows the adhesive material is applied in a forma sheet in asolid state, but the present disclosure is not limited thereto. Themethod proposed in the present disclosure is beneficial to increase thecaulking property of the adhesive material, and therefore, is beneficialto the robustness between each electronic unit and the substrate. Forexample, an adhesive material in a solid state is provided, and a sheetof the solid adhesive material is attached to a plurality of electronicunits. The sheet 131 may be an optical adhesive, such as optically clearadhesive (OCA). Please refer to the above descriptions for the detailsof the sheet 131, so they are not elaborated again.

Since the adhesive material 130 may be a liquid of an appropriateviscosity, the adhesive material 130 may flow into the spaces betweenthe chips and the substrate after the softened sheet 131 becomes theliquid adhesive material 130. For example, the adhesive material 130 mayslowly fill into and fill up the space 121S, the space 122S and thespace 123S by natural capillary phenomenon or gravity. In addition, theadhesive material 130 may also fill the gaps between the electronicunits and the pixel defining layers, or the adhesive material 130 maystay on the top surfaces of the electronic units. For example, theadhesive material 130 may stay on the top surface 121T of the electronicunit 121, on the top surface 122T of the electronic unit 122 or on thetop surface 123T of the electronic unit 123. The adhesive material 130may also stay on the top surfaces of the pixel defining layers. Forexample, the adhesive material 130 may stay on the top surface 151S ofthe pixel defining layer 151, on the top surface 152S of the pixeldefining layer 152 and on the surface 153S of the pixel defining layer153 or on the top surface 154S of the pixel defining layer 154. The topsurfaces of the electronic units may be higher than the top surface 130Sof the adhesive material 130 (shown in FIG. 2 ) after the adhesivematerial 130 fills the gaps between adjacent electronic units.

In some embodiments, the adhesive material 130 may further cover the topsurfaces of the electronic units. FIG. 7 illustrates that the adhesivematerial fills the spaces, fills the gaps between the electronic units,and covers the top surfaces of the electronic units. In someembodiments, a post process may be optionally carried out if theadhesive material 130 covers the top surfaces of the electronic units.FIG. 8 shows that the top surface 130S of the adhesive material 130 isas high as the top surfaces of the electronic units to form a coplanarstructure after the post process. The optional post process may be asurface leveling method. Please refer to FIG. 8 for the details of thepost process, so they are not elaborated again.

In some embodiments, a curing step of the adhesive material 130 may befurther carried out. An appropriate curing step may be carried out byreferring to the curing conditions of various adhesive materials 130,such as radiation, heating, or a mixture of the two, so that the curedadhesive material 130 may make the electronic units fixed on thesubstrate to reinforce the bonding strength between the electronic unitsand the substrate. Please refer to FIG. 6 , FIG. 7 or FIG. 8 for thedetails, so they are not elaborated again.

FIG. 13 is a schematic flowchart of the fifth embodiment of a method formanufacturing an electronic device according to the present disclosure,which shows a schematic cross-sectional view of the electronic device.In the fifth embodiment of the method of manufacturing an electronicdevice of the present disclosure, the method of applying the adhesivematerial may involve a sheet of a solid adhesive material or a liquidadhesive material.

The adhesive material 130 may slowly fill the space 121S, the space122S, and the space 123S after the adhesive material 130 is applied. Forexample, the adhesive material 130 may fill up the space 121S, the space122S, and the space 123S. In addition, the adhesive material 130 mayfurther fill the gaps between the electronic units and the pixeldefining layers. For example, the adhesive material 130 may fill the gapbetween the pixel defining layer 152 and the electronic unit 121, theadhesive material 130 may fill the gap between the pixel defining layer152 and the electronic unit 122, the adhesive material 130 may fill thegap between the pixel defining layer 153 and the electronic unit 122,the adhesive material 130 may fill the gap between the pixel defininglayer 153 and the electronic unit 123, and the adhesive material 130 mayfill the gap between the pixel defining layer 154 and the electronicunit 123.

Next, the adhesive material 130 may be cured. Different from theaforementioned curing of the adhesive material 130, the adhesivematerial 130 may be cured from the other side of the substrate 110 (theside opposite to the electronic units) in this embodiment. The method oflocally curing the adhesive material 130 may use a laser to focus oncertain parts of the adhesive material 130, or a local curing device tolocally cure certain parts of the adhesive material 130. For example, alaser may be used to focus on the part 135A, the part 135B, the part135C, the part 135D, the part 135E, the part 135F, the part 135G, thepart 135H and the part 135I of the adhesive material 130 so that theseparts of the adhesive material 130 are cured, but other parts of theadhesive material 130 are not cured or not completely cured, to become aselectively cured adhesive material 130 which is different from theabove-mentioned adhesive material 130.

The uncured adhesive material 130 or the incompletely cured adhesivematerial 130 may be removed after the selective curing of the adhesivematerial 130. The method to remove the uncured adhesive material 130 maybe: entirely cleaning the selectively cured adhesive material 130 orimmersing the selectively cured adhesive material 130 in a solvent, butthe present disclosure is not limited thereto.

An electronic device of this embodiment may be obtained after removingthe uncured adhesive material 130. The electronic device of thisembodiment includes a locally cured portion of the adhesive material.This locally cured portion of the adhesive material, such as the part135A, the part 135B, the part 135C, the part 135D, the part 135E, thepart 135F, the part 135G, the part 135H or the part 135I, may beselectively located in the space 121S, selectively located in the space122S or selectively located in the space 123S, but the presentdisclosure is not limited thereto. In addition, the locally curedportion of the adhesive material may also be selectively located in thegaps between the electronic units and the pixel defining layers, forexample, selectively located between the pixel defining layer 152 andthe electronic unit 121, selectively located between the pixel defininglayer 152 and the electronic unit 122, selectively located between thepixel defining layer 153 and the electronic unit 122, selectivelylocated between the pixel defining layer 153 and the electronic unit 123or selectively located between the pixel defining layer 154 and theelectronic unit 123, but the present disclosure is not limited thereto.The differences between the electronic device of this embodiment and theelectronic device 100A shown in FIG. 2 or the electronic device 101Ashown in FIG. 6 reside in that there may be no adhesive material 130remaining on the top surfaces of the electronic units or the adhesivematerial 130 may not stay on the top surfaces of the pixel defininglayers although the top surface 130S of the cured adhesive material 130may be lower than the top surfaces of the electronic units.

According to the method of manufacturing the electronic device of theembodiments of the present disclosure, an electronic device withenhanced bonding strength of the electronic units fixed on the substratemay still be obtained even the distance between the chips of theelectronic units and the substrate may be less than or equal to 3micrometers, or the gaps between the pixel defining layers and theadjacent electronic units may be less than 10 micrometers by applyingthe adhesive material in the spaces between the chips and the substrate.This electronic device may also be directly regarded as a packagingstructure. In this way, the quality of the mini electronic units in theelectronic devices may be improved to facilitate the technologicalimprovement and innovation of the electronic device.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the disclosure. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A method of manufacturing an electronic device,comprising: providing a substrate (110); providing an electronic unit(121) having a chip (121C) and at least one bonding pin (121A); mountingthe electronic unit (121) on the substrate (110) through the at leastone bonding pin (121A); and applying an adhesive material (130) into aspace (121S) between the chip and the substrate by a coating processafter mounting the electronic unit on the substrate.
 2. The methodaccording to claim 1, further comprising: curing the adhesive material.3. The method according to claim 2, wherein the adhesive material iscured by a heating process.
 4. The method according to claim 1, whereinthe adhesive material covers a top surface (121T) of the electronicunit, and a light transmittance of the adhesive material is greater thanor equal to 95%.
 5. The method according to claim 1, wherein theelectronic device is bonded to an optical substrate (130A) with anotheradhesive material (160).
 6. The method according to claim 5, wherein theoptical substrate comprises a color conversion layer, a color filterlayer (162A), and a bank (163) disposed besides the color conversionlayer and the color filter layer.
 7. The method according to claim 1,wherein the space between the chip and the substrate is less than orequal to 3 micrometers.
 8. The method according to claim 1, wherein thesubstrate comprises a pixel defining layer (154), the electronic unit islocated besides the pixel defining layer, and the adhesive material isapplied into a gap between the electronic unit and the pixel defininglayer.
 9. The method according to claim 8, wherein the gap between theelectronic unit and the pixel defining layer is less than 10 μm.
 10. Themethod according to claim 1, wherein the adhesive material has aviscosity in a range from 8 cP to 12 cP.
 11. The method according toclaim 1, wherein a light transmittance of the adhesive material isgreater than or equal to 95%.
 12. The method according to claim 1,wherein a top surface of the adhesive material is lower than a topsurface of the electronic unit.
 13. The method according to claim 1,wherein the electronic unit comprises a light emitting diode.